Building of prefabricated sections



March 17, 1970 K. E. E. ANDERssoN A3,500,596

BUILDING OF PREFABRICATED SECTIONS 2 Sheets-Sheet 1 Filed June 12. 1968 H nannumwwwummm,

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March 17, 1970 K. E. E. ANDERssoN 3,500,596 I BUILDING OF PREFABRIGATED SECTIONS Filed June 12. 1968 2 Sheets-Sheet` 2 United States Patent O 3 500,596 BUILDING F PRFABRICATED SECTIONS Karl Erik Evald Andersson, Dalangen, Jungskola, Sweden Filed June 12, 1968, Ser. No. 736,459 Claims priority, application Sweden, June 28, 1967, 9,398/ 67 Int. Cl. E04b 1/343, 1/88; E04c 2/32 U.S. Cl. 52-79 13 Claims ABSTRACT OF THE DISCLOSURE A building of prefabricated sections is provided comprising two complete end wall sections and a'number of intermediate sections therebetween, each such intermediate section comprising a complete assembly of a bottom joisting structure, two side wall structures and a roofforming top structure, and being of double-shell construction including an inner layer of corrugated sheet metal forming the supporting body structure and an outer layer of corrugated sheet metal attached thereto in spaced relationship, a heat insulation being provided between said inner and outer layers. All said inner and outer sheet metal layers being composed of trapezoidal-corrugated sheet metal bands of a particular cross section, said bands being interconnected at their ends by lap joints including bent band end portions and at their longitudinal edges by connecting elements of wood or the like. The bends in the sheet metal layers are of a particular design providing for stiffness and strength, and the top structure'of each intermediate section is, preferably, of a sheet metal framework construction capable of load distribution over the whole width of said mating side wall structures.

This invention relates to buildings of the type having a substantially rectangular base plan and being composed of prefabricated sections, viz two end wall sections and a number of intermediate sections connected in series therebetween, each such intermediate section comprising at its main coponents a bottom joisting structure, two opposed side wall structures, and a roof-forming top structure, which have all substantially the same width and are interconnected at their ends to form a frame-like unit. Although it is normally preferred to produce the end wall sections separately, each such end wall section may, if desired, be rigidly connected to a related intermediate section already in the factory.

Buildings of this general type are previously known and especially suited for ambulatory use, because they can easily be moved in sections from one site to another, if necessary. In addition, the sections of such buildings can be economically produced in large series, when suitably standardized, and the building size, i.e. in fact the length of the building, can readily be varied by adding or subtracting one or more intermediate sections, as required.

However, the known buildings of the type referred to are not particularly Well meeting the practical requirements for strength, stability, durability, easy maintenance and good insulating properties and further more they are rather difficult to assemble as Well as to then take apart for moving, because the sections are easily distorted because of lacking strength, or extremely heavy for their size due to complicated construction. Another disadvantage of the known buildings of the type in question is that their width, i.e. the length of each intermediate section, must ordinarily be kept within very narrow limits, if disturbing load supporting columns or partitions are to be avoided within the building.

It is, therefore, a general object of this invention to provide an improved building of the type referred to in which Patented Mar. 17, 1970 lCe said disadvantages are all eliminated and which is also resistant to lire, rot and insect attacks. Further and more specific objects of the invention are to provide a building of the type in question which permits convenient and concealed installation of electric wiring as well as Water conduits, and the interior decoration of which can be easily varied and adapted for various purposes. A further important object of the invention is to provide a building as defined in which an efficient ventilation can be arranged and any desired indoor climate may conveniently be maintained by means of air conditioning equipments.

The most important feature of a building embodying the invention is that each of said main components of each intermediate section comprises a room-enclosing inner layer of corrugated sheet metal having its corrugations extending in parallel with the side edges of the related section, said inner component layers forming together the supporting body structure of the building, and, secured to the outside of each such inner layer and spaced therefrom, a rigid outer layer forming a facade face, a joisting bottom cover and a roof face, respectively, the interspace between said inner and outer layers being at least partly filled with the insulating material and said inner layers in at least the two side wall structures and the bottom joisting structure being adapted to receive on their insides coveringpanels forming the inner walls and the floor. In this manner an extreme structural rigidity and Istrength can be obtained with a minimum of weight.

In a preferred form of the building embodying the invention the corrugated sheet metal layer in at least the bottom joisting structure and the two side Wall structures are in line with one another, and each such corrugation groove in the bottom joisting structure communicates at its ends with corresponding grooves in the side wall structures. This will create an open channel system for convenient ventilation and draftless heat control of the interior of the building and also provide for easy installation of electric wiring, water conduits and the like.

Another important feature of the building embodying the invention is that all incorporated corrugated sheet metal layers are composed of interconnected sheet metal strips or bands corrugated in their longitudinal direction and of a particular and uniform cross section throughout, as will more clearly appear from the following. In this way considerable rationalization gains may be achieved in connection with large-scale factory production of the buildings.

Further objects and features of the invention will appear from the following description of an embodiment thereof, which is illustrated in the accompanying drawings wherein:

FIG. l shows in perspective and in a very diagrammatical form the general division of a building according to the invention into sections to be prefabricated,

FIG. 2 is a more detailed but still very simplified sectional elevation of the building (without end wall section),

FIG. 3 is a cross-section on a larger scale of a corrugated sheet metal strip or band which in various lengths is used as an essential structural element throughout the building shown,

FIG. 4 is a partial horizontal section through two outer wall portions of the building meeting at an outer corner thereof,

FIG. 5 is an enlarged and more detailed partial sectional elevation corresponding to the left hand part of FIG. 2,

FIG. 6 is a partial and compacted longitudinal sectional elevation of the same building (substantially as viewedY from the right in FIG. 5) and showing also the one end wall of said building,

FIG. 7 shows on a larger scale a partial sectional elevation of a room-enclosing, corrugated sheet metal layer in the building and is specifically illustrating the attachment of the removable covering panels on the inside thereof, and

FIG. 8 is a partial perspective view illustrating how certain of the corrugated sheet metal elements in the -building are locally cut throughV and :bent before being jointed to other corrugated sheet metal elements.

As appears from FIG. l the illustrated building has a substantially rectangular base plan and is composed of two end wall sections, generally designated by G, and an arbitrary number of-in FIG. 1 threeintermediate sections, generally designated by M, the latter being on a suitable foundation (not shown) interposed between the end wall sections G and connected to them as well as to one another to form a building of desired size. It will beunderstood that this building can, when required, again lbe taken apart into said sections and that the size of each such section has been chosen with a view to facilitate their transport. As far as their general construction is concerned and apart from possible doors and windows `(not shown) the two end wall sections G are mirror pictures of each other and substantially at. Apart from possible windows and doors, partition walls and special equipment parts, also the intermediate sections M are identical as far as their general construction is concerned but they may be of different width counted in the longitudinal direction of the building, if so required. Each intermediate section M thus comprises as its main components a bottom joisting structure or part A, two opposed side wall structures or parts B and a roof-forming top structure or part C, the latter forming in the present case a ridged roof.

'-.As may be seen from the sectional elevation of FIG. 2 each intermediate section M may be considered to be a sort of double-shell construction, the interior of the building, i.e. commonly the dwelling space, being primarily surrounded by an inner, room-enclosing layer of corru- 'gated sheet metal, which in fact constitutes the supporting body structure of the building. In the side wall structures Blthis inner sheet metal layer isdesignated by 1 and is composed of vertically extending and vertically corrugated sheet metal strips, as will appear more closely from the following. In the bottom joisting structure A the corresponding innerlayer of corrugated sheet metal is designated by 2 and is for rigidity united back to back with an underlying second layer 3 of` corrugated sheet metal. As will appear from the following, also these layers 2 and 3 are composed of corrugated sheet metal strips placed side by side and their corrugations extend in the direction between the side walls B.

'Ihe inner layer 4 of the top structure C is likewise composed of corrugated sheet metal strips having their corrugations extending in the direction between the side walls B and this latter layer 4 forms a bottom portion of.a framework construction, which further comprises two upper and oppositely inclined corrugated sheet metal layers 5 rigidly interconnected to form a roof ridge and being composed in the same manner as the layer 4 of strips having their corrugations extending in the direction ofthe roof slope. A number of connecting struts 6, 7 are provided between the frameworak bottom layer 4 and the.upper inclined layers 5, and these struts are likewise made of corrugated sheet metal strips with their corrugations extending in the direction between said layers 4 and 5. Preferably these struts 6, 7 are of the same width as the rest of the intermediate section and composed of pieces of corrugated sheet metal strips of the same kind as used for the other sheet metal layers.

The outer end edges of the inclined sheet metal layers 5 are rigidly connected t@ the corresponding end edges of the sheet metal layer 4 and also to the upper end edges of the .inuershet metal layers t of the side walls B, and

the latter are in turn rigidly connected at their lower ends to the outer ends of the sheet metal layer 2 of the bottom joisting structure A. Thanks to the framework construction of the top structure C, the reinforcement of the sheet metal layer 2 of the bottom joisting structure, obtained iby the provision of the lower sheet metal layer 3, and the rigid interconnection of all the sheet metal layers constituting the inner supporting body structure, a very good stability and a high load-carrying capacity of the latter are secured. A particular advantage of the described construction is the roof-load distributing function performed by the framework-type top structure.

Outside the inner shell described there is all over an interspace illed with a suitable heat insulating material I, which can to advantage consist of mineral wool or some other incombustible and porous material. Outside the heat insulation is an outer shell, the various parts of which are also made of corrugated sheet metal and built up of the same special type corrugated sheet metal strips as are used for the inner, supporting structure. In the side wall structures B this outer layer 8 forms a facade face with vertically extending corrugations, while the corresponding outer sheet metal layer 9 in the bottom -joisting structure A forms a joisting bottom cover. The latter, in fact, serves as a load transmitting element between the inner supporting structure and a foundation, the supporting walls or girders of which are indicated at F. Finally, the sheet metal layers 10, which are part of the outer shell and belong to the top structure C form the external roof face having its corrugations extending in the direction of the roof slope. Built up in this manner the intermediate section M is complete from joisting bottom cover to external roof face.

As far as their general construction is concerned, the end wall sections G are substantially identical with the side wall structures B of each intermediate section M, although of course of considerably larger dimensions. Besides, the end wall sections are lacking, for obvious reasons, the rigid connection with adjacent parts and are instead adapted to be -joined in a simple and detachable way to the adjacent intermediate section M, preferably through boltings, unless it is preferred to combine each end wall section with the adjacent intermediate section already in the factory. As can be seen from FIGS. 4 and 6 echend wall section G thus consists 0f an inner layer 11 composed of corrugated sheet metal strips placed on end 'and side by side with vertically extending corrugations, and of an outer, similarly constructed corrugated sheet metal layer 12. Between these layers is a heat insulation I, and, as is the case also in the side wall structures B, a diffusion-tight -lm is preferably provided on the` inside of the insulation. This ilm can, however, be dispensed with in certain cases. At the lower edge of each end wall section a rigid connection between the inner sheet metal layer 11 and the outer sheet metal layer 12 is provided through double bending of the inner sheet metal layer 11, as shown at 13 in lFIG. 6, while the sheet metal layers are held together at their top by a bar 14, which extends along the upper edge and is covered at the erection of the building by a sheet metal chute 15 forming a barge board and a roof edge covering.

As has been pointed out already, the various sheet metal layers in the building are composed of corrugated stripsA or bands vof sheet metal placed side by side, for instance sheets of aluminum or of iron or steel which has been subjected to an anti-corrosive treatment such as galvanization and has possibly been lacquered. The sheet metal strips are all of the same cross section, and FIG. 3 shows a preferred form thereof. In the various figures such strip or band has been identified by the reference D. As clearly appears from FIG. 3 the sheet metal strip D is provided with outwardly directed flange-like edge portions a lying in one and the same plane and projecting at right angles each from an inner margin b which in its turn forms a right angle with the main plane of the strip and merges, likewise under a right angle, into a web portion or strip bottom c-d, in which there is formed a plurality of trapezoidal waves or corrugations e rising between the marginal portions b and having their top portions substantially flush with the two ange-like edge portions a. For reasons appearing from the following, the cross section of the strip is so shaped that the width of each web or strip bottom portion c located between one of the marginal portions b and the adjacent trapezoidal wave e is somewhat larger than the width of the remaining web or strip bottom portions d located between each two adjacent waves e, said latter web or strip bottom portions d being of equal width, which is preferably the same as the width of the flat top sides of the trapezoidal waves. Of course, the terms bottom and top side used in connection with the description of FIG. 3 has nothing to do with the position of the sheet metal strip in the building. It should also be observed that the strips D appearing in FIGS. 4 and 6 have not been shown with their full width for the sake of saving drawing space.

As appears from FIG. 4 the sheet metal strips D forming the inner layers 1 and 11 and the sheet metal strips forming the outer facade layers 8 and 12 in the end wall sections G and in the side wall structures B of each intermediate section M are placed on their ends in back to back relationship and interconnected in pairs by means of vertical spacing bars 16, which extend between the flange portions a of the two sheet metal strips and are connected in a suitable manner to the latter as well as to the related marginal portions b of the sheet metal strips. The bars 16 are preferably made of pressureimpregnated wood but may also be made of any other suitable material having a low heat conductivity. Each pair of opposed sheet metal strips D together with the related pair of spacing bars 16 and the dilling of heat insulation I therebetween can be considered as a primary construction unit in the building, and each end wall section G as well as each side wall structure B of each intermediate section M is normally composed of a plurality of such units placed side by side and joined together into larger assemblies through boltings 17 between adjacent bars 16. Externally the joints between the primary construction units are covered by sheet metal chutes 18 of trapezoidal cross section and of the same shape as one of the waves or corrugations of the sheet metal strip. Thanks to the special configuration of the sheet metal strip the chutes 18 will cover also the boltings 17 and give the facade wall a uniform appearance. The same 4joining method can be used also between the various intermediate sections M of the building, lalthough in this case the bolting takes place at the building site. When window or door openings of larger width than the individual sheet metal strips are provided in the walls, such openings must, of course, be framed appropriately so that the insulation material I cannot fall out and the window and door frames can be fastened in a convenient manner.

As appears from the upper part of FIG. 6 the sheet metal strips incorporated in the upper sheet metal layer 5 of the top structure framework are united with the corresponding sheet metal strips forming the roof layer in the same manner as previously described and this by means of bars 16 standing on their edges and positioned in line with the corresponding bars in the side wall structures B. Also in this case the joining of the primary construction units is effected by means of boltings 17, and the joints are covered on the upper side by inverted sheet metal chutes 18 corresponding to those used on the facade walls. To avoid a depression of the sheet metal strips D of the roof, e.g. because of snow loads, a number of wooden ridges 19 is placed on edge between the sheet metal layers 5 and 10, each such ridge having a length equal to the distance between adjacent bars 16 and having its ends connected to the latter in a suitable manner to constitute rigid frames. Of course, girder elements corresponding to the ridges 19 can be used also in the wall structures, but this will normally be unnecessary.

As is best seen from FIG. 6 the construction of the bottom joisting structures A diters in some essential respects from the construction of the walls. Thus, as has already been pointed out, the inner or upper layer 2 of corrugated sheet metal strips D is reinforced by means of an immediately under-lying further additional sheet metal layer 3, and more specifically in such a way that two sheet metal strips in back to back relationship are interconnected by riveting, spot welding or the like at several points between their edges and also connected along their edges to battens 20 extending between them. Of course, the primary construction units thus formed are of the same width as the corresponding primary construction units of the other parts of the building and are interconnected in side by side relationship by means of boltings 17 similar to those used in the walls. However, the most essential difference is that the two co-operating bottom joisting sheet metal layers 2 and 3 are united with the joisting bottom cover 9 exclusively with the aid of a -few supporting joists 21, the upper and lower edges of which are proled to ll up the corrugations of the sheet metal layers 3 and 9. The joists 21 of each intermediate section M are of a length equal to the width of the section and these joists are thus the only connecting elements passing through each intermediate section in the longitudinal direction of the completed building. The joisting bottom cover 9, is in its turn, composed of single sheet metal strips D having wooden `battens 22 secured to their edges and being interconnected by means of boltings 17. The joisting bottom `cover 9 has, of course, for its main purpose to carry the joist insulation I, but also to form part of the external shell of the building as already explained.

The ceiling layer 4 is built up in the same way as the joisting bottom cover 9 from single sheet metal strips D with wooden edge battens 22 held together by boltings 17. .It should be kept in mind, however, that the ceiling layer 4 forms part of the previously described framework construction and is thus stiifened and supported through its connection with the inclined sheet metal layers 5 via the struts 6 and 7.

The inner sheet metal layers 1, 2, 4, and 11, respectively, are adapted to receive on their insides, i.e. the surfaces facing the interior of the building, covering panels capable of forming internal walls, oor and ceiling of necessary smoothness and desired finish. The bottom joisting structure A is thus covered with panels 25 which are fastened by suitable means and forming the floor, while the underside of the sheet metal layer 4 is covered with suitable ceiling panels or boards 26, which are, preferably, exchangeably attached. Corresponding wall panels 27 cover the insides of the outer wall portions of the building, and particularly these wall panels 27 can to advantage, as shown in FIG. 7, have hook-shaped, horizontally extending attachment ribs 28 secured to their backs which can be hooked on to tongues 29 that are punched and bent out of the corrugation tops of the inner sheet metal layers 1 and 11. These tongues are easy to produce and eliminate the necessity for loose attachment means, such as screws or rivets. Of course, similar tongues can be used to hold the ceiling panels 26. Since the panels 26 and 27 are easily detachable they can be factory-made to suit different tastes, and with such panels any necessary renovation or alternation of the building interior can be accomplished quickly and with a minimum of handicraft work.

Like the width of each intermediate section is preferably a whole multiple of the width of the sheet metal strip D, also the length of each intermediate section is suitably determined by said strip width in such a manner that the outermost bars 16 of each end wall section G can be joined to their respective side wall structures B of the adjacent intermediate section M at each building corner in the manner shown in FIG. 4. Here the bars 16 are interconnected by means of bolts and angle-irons 30, and after insertion of suitable heat insulation material I the corner is covered witha sheet metal chute 31, the side edges of which are secured over the outer edges of the bars 16 to complete the pattern of the sheet metal strips of the facade layers 8 and 12. Of course, the corner formed by the sheet metal chute 31 can be reinforced in any suitable way, if necessary. The previously mentioned, barge-board-forming sheet metal element or chute 15 is, of course extended so as to cover the upper end of the corner and, when necessary, the corner can also be provided with a bottom plate of wood or sheet metal.

As will be obvious from the foregoing, all sheet metal strips incorporated in the inner layers 1, 2 and 4 of each intermediate section M are so located that their flange-like edge portions a are facing inwardly toward the panels 27, 25 and 26, respectively, and are lying on a line with one another in said layers. This means that also the corrugation grooves between the waves e are registering and are mutually communicating at their ends inside the panels, as indicated by the arrows 32 in FIG. 5. The corrugations thus form an open channel system which not only allows concealed installation of electric wiring inside the panels but also olers good possibilities of ventilation and circulation of heated or cooled air, for instance from an air conditioning equipment (not shown) which may suitably be located above the layer 4 and between the struts 7. In such a case the sheet metal layer 4 is, of course, provided with suitable apertures for the air, and admittance of fresh air as well as discharge of polluted air can to advantage take place through apertures (not shown) in the upper parts of the end wall sections G. It will-be obvious, however, that the building according to the invention can also be heated in a concentional manner by means of a central heating plant or electric heating sources.

In the manufacture of the described building it has proved particularly advantageous to unite the sheet metal layers forming part of the inner and outer shells of the intermediatesections M, i.e. actually the sheet strips D, through lap joints, which are conveniently rivited-prefera-bly with so-called blind rivets--or spot-welded. Thls applies particularly to the joints between the sheet metal layers 1 and 2,`and the sheet metal layers 1 and 4 as well as 5 in the inner shell and the joints between the sheet metal layers 8 and 9 and 10 respectively in the outer shell, but also to the joint between the inner and outer sheet metal layers 11 and 12 of the end wall sections G, as shown at 13 in FIG. 6. A condition for the use of such lap joints is, however, that the individual sheet metal strips D can be bent, which is preferably done in the way shown in FIG. 8.

As appears from the lower part of this latter ligure, the strip bottom parts c and d respectively are cut through right down to the insides of the tops of the waves, e as indicated at 34, and this in line with the desired bending line 35, which should be at least substantially at right angle to the corrugations of the sheet metal strip. Secondary slots `36 are then cut from the primary slots 34 along the side edges of the strip bottom parts c and d, and the length of these secondary slots should approximately equal the profile height of the sheet metal .strip when a right angle bend is desired. The lugs thus formed between the slots 36 on either side of the slots 34v are bent slightly downward, and at the same time it must be ascertained that the side wall portions of the corrugations ball inside each other during the bending operation. .As seen from the upper part of FIG. 8, these side Iwall portions will overlap each other after accomplished bending so that they can 'be conveniently united by rivets 37, while the abovementioned lugs can suitably be folder together as indicated at 38, although even here riveting or pointwelding may be used. A right angled bend in the corrugated sheet metal strip D carried out in the described manner is very strong. In general the same method may,

ofcourse, 'be used to produce an acute or an obtuse bend. Double-bending is necessary only at the lower edge 13 of the end wall sections G, whereas the sheet metal layers 2, 4, 58 and 9 all have single-bends only.

Obviously the details of the building thus described and shown can be modified in many ways. By way of example, the building may have a pent roof instead of a ridged roof, in which case the framework construction of the top structure C may be entirely dispensed With, particularly in biuldings of moderate width.

What is claimed is:

1. A Ibuilding having a substantially rectangular base plan and being composed of prefabricated sections, said section comprising two end wall sections an a number of intermediate sections connected in series therebetween, each such intermediate section comprising as its main components a bottom joisting structure, two opposed side wall structures, and a roof-forming top structure, which have all substantially the same width and are interconnected at their ends to form a frame-like unit, and wherein each of the said main components of each intermediate lsection comprises a room-enclosing inner layer of corrugated sheet metal having its corrugations extending in parallel with the side edges of the related section, said inner component layers forming together the supporting body structure of the building, and, secured to the outside of each such inner layer and spaced therefrom, a rigid outer layer forming a facade face, a joisting bottom cover and a roof face, respectively, the interspace between said inner and outer layers being at least partly filled with insulating material and said inner layers in at least the two side Wall structures and the bottom joisting structure being adapted to receive on their insides covering panels forming the inner walls and the lloor.

2. A building according to claim 1, wherein the corrugation grooves on the inside of the inner corrugated sheet metal layer in at least the bottom joisting structure and the two side wall structures are in line with one another, and with each such corrugation groove in the bottom joisting structure communicating at its ends with corresponding grooves in the side wall structures.

3. A building according to claim 1, wherein said inner corrugated sheet metal layer of each side wall structure is rigidly secured by means of vertically extending spaclng .bars of a material having a low heat conductivity to a secondrcorrugated sheet metal layer forming said facade face and having likewise its corrugations extending in the vertical direction.

4. A building according to claim 1, wherein said inner corrugated sheet metal layer of the bottom joisting structureis united back to back with an underlying second corrugated sheet metal layer, said united layers being in turn connected to and supported at some distance above a joisting bottom cover by means of joists made of a material having a low heat conductivity and extending transversally to the corrugations of said sheet metal layers, the heat insulating material being interposed between said second sheet metal layer and the kjoisting bottom cover.

5. A building according to claim 4, wherein said joisting bottom cover is also made of corrugated sheet metal.

` 6. A building according to claim 1, wherein said inner corrugated sheet metal layer of the roof-forming top structure forms a bottom portion of a framework construction, which further includes twol upper corrugated sheet metal layers inclined in opposite directions to form a roof ridge and having their corrugations extending in the direction of the roof slope, said upper layers being rigidly interconnected at their inner ends and having their respective outer ends secured to the corresponding outer vends of said inner layer, a number of connecting strut members being interposed between said sheet metal layers to stillen the framework,

7. A building according to claim 6, wherein said connecting strut members are also made of corrugated sheet metal having its corrugations extending in the direction between said inner and upper sheet metal layers, said strut members having a width corresponding to that of said framework construction.

8. A building according to claim 6, wherein said upper corrugated sheet metal layers forming the roof ridge are rigidly connected by means of spacing bars and girders of a material having a low heat conductivity to an upper roof layer which is likewise made of corrugated sheet metal having its corrugations extending in the direction of the roof slope, the heat insulating material being interposed between said upper sheet metal layers and said roof layer.

9. A building according to claim 1, wherein said inner corrugated sheet metal layers of each intermediate building section present substantially trapezoidal corrugations and are, at the corners between the bottom joisting structure and the side wall structures and between the latter and the roof-forming top structure, respectively, connected to one another by lap joints, at least the one sheet metal layer at each such joint presenting an end portion which, after having been locally cut through, is bent out from the main plane of its related sheet metal layer along a line extending across the corrugations thereof.

10. A building having a substantially rectangular base plan and being composed of Prefabricated sections, said section comprising two end wall sections and a number of intermediate sections connected in series therebetween, each such intermediate section comprising as its main components a bottom joisting structure, two opposed side wall structures, and a roof-forming top structure, which have all substantially the same width and are interconnected at their ends to form a frame-like unit, and wherein each of the said main components of each intermediate section comprises a room-enclosing inner layer of corrugated sheet metal having its corrugations extending in parallel with the side edges of the related section, said inner component layers forming together the supporting body structure of the building, and, secured to the outside of each such inner layer and spaced therefrom, a rigid outer layer likewise of corrugated sheet metal having its corrugations extending in parallel with the side edges of the related section, said outer component layers forming facade faces, a joisting bottom cover and a roof face, respectively, the interspace between said inner and outer layers being at least partly lled with insulating material and said inner layers in at least the two side wall structures and the bottom joisting structure being adapted to receive on their insides covering panels forming the inner walls and the floor, all said corrugated sheet metal layers presenting substantially trapezoidal corrugations and being connected to adjacent layers by lap joints, at least the one sheet metal layer at each such joint presenting an end portion which, after having been locally cut through, is bent out from the main plane of its related sheet metal layer along a line extending across the corrugations thereof.

11. A building according to claim 11, wherein at least some of said inner corrugated sheet metal layers are provided on their inside with attachment means for removably retaining said covering panels.

12. A building according to claim 11, wherein said attachment means are tongues punched out from tne sheet metal layers themselves and -bent into hooks t'or cooperation with hook-like attachment ribs secured to the back yof each covering panel.

13, A building according to claim 10, wherein all incorporated corrugated sheet metal layers are composed of longitudinally corrugated sheet metal strips of a uniform cross section presenting outwardly directed uniplanar flange-like edge portions projecting at right angles from marginal portions which in their turn form right angles with the main plane of the strip and merge into a web portion in which there is formed a plurality of trapezoidal corrugations, each having its top portion substantially flush with said flange-like edge portions of the strip, the width of those parts of the web portion, which separate the respective marginal portion from their adjacent corrugations, being silghtly larger than the width of those parts of the web portion, which separate two adjacent corrugations, the latter parts of the web portion being substantially uniform in width.

References Cited UNITED STATES PATENTS 2,330,819 10/1943 Faure et al. 52-90 2,706,313 4/1955 Radman 52-79 2,722,901 11/1955 Johnson et al. 52-90 3,059,734 10/1962 Tripp 52-618 X 3,102,610 9/ 1963 Shelby 52--220 X 3,156,070 11/ 1964 iMesnager 52-630 X 3,184,012 5/1965 -Fujishima et al 52-90 3,196,773 7/1965 Lorenz et al. 52-630 X HENRY C. SUTHERLAND, Primary Examiner PRICE C. FAW, IR., Assistant Examiner U.S. C1. X.R. 

